Storing grain in PET bottles - can I use CO2 instead of oxygen absorber?

[Omega]

I like brewing ales and making wine, so I have PET bottles, sanitiser, CO2 cylinder and Carbonation Cap Tee Piece Kit https://brewkegtap.co.uk/products/carbo ... o4QAvD_BwE
And I have grains for making my drinks - wheat, barley, rice, corn...
I wonder if I can replace oxygen absorbers with CO2 in bottles to store grains. I googled the topic, but saw information for only industrial operations. CO2 is slightly heavier than air, so it should stay in the bottle once added there
Thanks

[GillyBee]

How long are you planning to store these? PET is gas tight for short/medium storage or the big soft drinks firms would not touch it but I do not know how many years it will last before becoming permeable.
As for using CO2. In theory I would expect it to work but you would need to be careful to avoid any condensation forming in the bottle or your grain may want to germinate.
The reason to remove the oxygen is to remove one essential needed for both bug growth and oxidation of fats. Chlorophyll converts CO2 to oxygen. The grain should not be doing anything but I do not know if there are any other bugs/components in grain that might be able to break down CO2.

[Omega]

Probably store for about 2 years, 5 maximum - I will use grain by then. Is it better then to store in mylar bags or vacuum? I like the idea of PET because I can repack it back with CO2 if I don’t use all grain